电极组件和电池Electrode assembly and battery
技术领域Technical field
本申请涉及电池领域,尤其涉及一种电极组件和具有该电极组件的电池。This application relates to the field of batteries, and in particular to an electrode assembly and a battery with the electrode assembly.
背景技术Background technique
一般卷绕式电池在收尾时,电芯外层极片尾部都存在部分空铝箔(两面均无活性物质涂层),电芯一般使用铝塑膜进行密封包装,并且电芯与密封包装电芯的外壳之间存在间隙。此类电芯在遭受重物冲击时,由于铝塑膜外壳一般具有较好的延展性而不会断裂或者不完全断裂,但电芯自身会出现破裂,破碎形成的碎屑尤其是外圈的空铝箔产生碎屑在外壳的包裹束缚下,与电芯破碎的极片接触,导致短路发热甚至起火爆炸等事件发生。Generally, when winding batteries are finished, there are partially hollow aluminum foils at the end of the outer pole piece of the battery (no active material coating on both sides). The battery is generally sealed and packaged with aluminum-plastic film, and the battery is sealed with the battery. There is a gap between the shells. When this type of battery is impacted by a heavy object, because the aluminum-plastic film shell generally has good ductility, it will not break or incompletely break, but the battery itself will rupture, and the debris formed by the crushing, especially the outer ring The debris generated by the empty aluminum foil is in contact with the broken pole piece of the battery under the wrapper of the shell, resulting in short-circuit heating and even fire and explosion.
发明内容Summary of the invention
鉴于上述状况,有必要提供一种外层无空铝箔、安全性能好的电极组件和具有该电极组件的电池。In view of the above situation, it is necessary to provide an electrode assembly with a non-voided aluminum foil on the outer layer, good safety performance, and a battery with the electrode assembly.
本申请实施例提供了一种电极组件,包括第一极片、第二极片和隔离膜,所述第一极片与所述第二极片的极性相反,所述隔离膜设置于所述第一极片和所述第二极片之间,所述电极组件由所述第一极片、所述隔离膜和所述第二极片卷绕形成。所述第一极片包括第一集流体和第一活性物质层,所述第一活性物质层设置于所述第一集流体表面,所述第一极片的卷绕终止端位于所述第二极片的卷绕终止端远离卷心的外侧,所述第一极片的卷绕终止端上的所述第一活性物质层覆盖所述第一集流体朝向所述第二极片的一侧表面, 所述第一极片的卷绕终止端上的所述第一集流体背离所述第二极片的一侧表面未涂覆所述第一活性物质层。所述电极组件进一步包括第一粘接件,所述第一粘接件设置于所述电极组件的外表面。The embodiment of the present application provides an electrode assembly, including a first pole piece, a second pole piece, and an isolation film. The first pole piece and the second pole piece have opposite polarities, and the isolation film is disposed at all Between the first pole piece and the second pole piece, the electrode assembly is formed by winding the first pole piece, the isolation film, and the second pole piece. The first pole piece includes a first current collector and a first active material layer, the first active material layer is disposed on the surface of the first current collector, and the winding end of the first pole piece is located at the first The winding end of the second pole piece is far away from the outside of the winding core, and the first active material layer on the winding end of the first pole piece covers one of the first current collectors facing the second pole piece On the side surface, the first active material layer is not coated on the side surface of the first current collector on the winding termination end of the first pole piece away from the second pole piece. The electrode assembly further includes a first adhesive member disposed on an outer surface of the electrode assembly.
在一可选实施例中,所述第一粘接件为半液体粘性材料,以点涂、涂覆等方式设置于所述电极组件的外表面。In an optional embodiment, the first adhesive member is a semi-liquid viscous material, and is disposed on the outer surface of the electrode assembly by means of spot coating, coating, or the like.
在一可选实施例中,所述第一粘接件的厚度小于或等于20um。In an optional embodiment, the thickness of the first adhesive member is less than or equal to 20 um.
在一可选实施例中,所述电极组件还包括第二粘接件,所述第一粘接件连接所述第二粘接件,所述第二粘接件连接所述第一极片的卷绕终止端并覆盖所述电极组件的部分外表面。In an optional embodiment, the electrode assembly further includes a second adhesive member, the first adhesive member is connected to the second adhesive member, and the second adhesive member is connected to the first pole piece The winding termination end of the electrode assembly covers part of the outer surface of the electrode assembly.
进一步地,所述第二粘接件的厚度为15um~25um。Further, the thickness of the second adhesive member is 15um-25um.
在一可选实施例中,所述第二极片的卷绕终止端沿卷绕方向伸出所述第一极片的卷绕终止端。In an optional embodiment, the winding end of the second pole piece extends from the winding end of the first pole piece in the winding direction.
进一步地,所述隔离膜的卷绕终止端沿卷绕方向伸出所述第二极片的卷绕终止端。Further, the winding termination end of the isolation film protrudes from the winding termination end of the second pole piece in the winding direction.
在一可选实施例中,所述电极组件还包括第一极耳和第二极耳,所述第一极耳连接所述第一极片,所述第二极耳连接第二极片,沿所述电极组件的厚度方向,所述第一极耳与所述第二极耳的投影不重叠。In an optional embodiment, the electrode assembly further includes a first tab and a second tab, the first tab is connected to the first pole piece, and the second tab is connected to the second pole piece, Along the thickness direction of the electrode assembly, the projections of the first tab and the second tab do not overlap.
进一步地,所述第一极片的卷绕起始端设有第一空箔区,所述第二极片的卷绕起始端设有第二空箔区,所述第一极耳设置于所述第一空箔区,所述第二极耳设置于所述第二空箔区。Further, the winding start end of the first pole piece is provided with a first empty foil area, the winding start end of the second pole piece is provided with a second empty foil area, and the first tab is arranged on the In the first empty foil area, the second tab is arranged in the second empty foil area.
进一步地,所述电极组件包括第一绝缘件,所述第一绝缘件设置于所述第一空箔区并覆盖所述第一极耳。Further, the electrode assembly includes a first insulating member disposed in the first empty foil area and covering the first tab.
在一可选实施例中,所述第一粘接件的粘接力为100-1000N/m,拉伸断裂应力小于或等于4000N/m。In an optional embodiment, the adhesive force of the first adhesive member is 100-1000 N/m, and the tensile fracture stress is less than or equal to 4000 N/m.
本申请的实施例还提供一种电池,包括电极组件和包装体,所述电极组件为上述任一项所述的电极组件,所述电极组件收容在所 述包装体中,所述电极组件的极耳伸出所述包装体。The embodiments of the present application also provide a battery, including an electrode assembly and a packaging body, the electrode assembly is the electrode assembly described in any one of the above, the electrode assembly is housed in the packaging body, the electrode assembly The tabs extend out of the packaging body.
上述电极组件将第一裁切部作为收尾端,使电芯组件最外圈的极片没有空铝箔的设计,节省单个电芯铝箔的耗材,并且大大减少了产生铝碎屑的可能,从而大量消除碎屑导致的危险短路,避免电芯起火爆炸的危险发生,提高电芯在遭受极端使用情况下的安全性能。电极组件表面还设置第一粘接件,当电极组件装于包装袋时,第一粘接件可以将电极组件外表面与包装袋粘接起来。在遭受跌落、撞击等外力时,电极组件与外部包装袋可以紧密连接在一起,二者之间无相对位移,减少剪切破坏。The above-mentioned electrode assembly uses the first cut part as the finishing end, so that the pole piece of the outermost circle of the cell assembly does not have the design of empty aluminum foil, which saves the consumables of the aluminum foil of a single cell, and greatly reduces the possibility of aluminum debris. Eliminate the dangerous short circuit caused by debris, avoid the danger of fire and explosion of the battery, and improve the safety performance of the battery under extreme conditions of use. The surface of the electrode assembly is also provided with a first adhesive member. When the electrode assembly is installed in the packaging bag, the first adhesive member can bond the outer surface of the electrode assembly with the packaging bag. When subjected to external forces such as a drop or impact, the electrode assembly and the external packaging bag can be tightly connected without relative displacement between the two, reducing shear damage.
附图说明Description of the drawings
图1为电极组件在一实施例中的卷绕结构示意图。FIG. 1 is a schematic diagram of a winding structure of an electrode assembly in an embodiment.
图2为电极组件在一实施例中的卷绕结构示意图。FIG. 2 is a schematic diagram of a winding structure of an electrode assembly in an embodiment.
图3为电极组件在一实施例中的结构示意图。FIG. 3 is a schematic diagram of the structure of an electrode assembly in an embodiment.
图4为第一极片在一对比实施例中的展开结构示意图。Fig. 4 is a schematic diagram of the expanded structure of the first pole piece in a comparative embodiment.
图5为第一极片在一实施例中的展开结构示意图。Fig. 5 is a schematic diagram of the expanded structure of the first pole piece in an embodiment.
图6为第一极片在一对比实施例中的展开结构示意图。Fig. 6 is a schematic diagram of the expanded structure of the first pole piece in a comparative embodiment.
图7为第一极片在一实施例中的展开结构示意图。Fig. 7 is a schematic diagram of the expanded structure of the first pole piece in an embodiment.
图8为电极组件在一对比实施例中的卷绕结构示意图。FIG. 8 is a schematic diagram of the winding structure of the electrode assembly in a comparative embodiment.
图9为电池在一实施例中的结构示意图。FIG. 9 is a schematic diagram of the structure of a battery in an embodiment.
主要元件符号说明:Symbol description of main components:
电极组件 100 Electrode assembly 100
第一平面 101 First plane 101
第二平面 102The second plane 102
第一弧面 103The first arc 103
第二弧面 104The second arc 104
空铝箔 105 Empty aluminum foil 105
绝缘胶带 106 Insulating tape 106
第一极片 10The first pole piece 10
第一集流体 11The first episode of fluid 11
第一活性物质层 12The first active material layer 12
卷绕终止端 13Winding termination end 13
第一空箔区 14The first empty foil area 14
第二极片 20The second pole piece 20
第二集流体 21The second episode of fluid 21
第二活性物质层 22The second active material layer 22
第二空箔区 23The second empty foil area 23
隔离膜 30 Isolation film 30
卷绕终止端 31Winding termination end 31
第一粘接件 41The first bonding part 41
第二粘接件 42The second bonding part 42
第一极耳 50 First pole ear 50
第二极耳 60The second pole ear 60
第一绝缘件 70 First insulation piece 70
第二绝缘件 80 Second insulation piece 80
电池 200 Battery 200
包装体 201 Packaging body 201
具体实施方式:Detailed ways:
下面将结合本申请实施例中的附图,对本申请实施例中的技术方案进行清楚、完整地描述,显然,所描述的实施例仅是本申请一部分实施例,而不是全部的实施例。基于本申请中的实施例,本领域普通技术人员在没有做出创造性劳动前提下所获得的所有其他实 施例,都属于本申请保护的范围。The following will clearly and completely describe the technical solutions in the embodiments of the present application with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in this application, all other embodiments obtained by those of ordinary skill in the art without creative work shall fall within the protection scope of this application.
需要说明的是,当元件被称为“固定于”另一个元件,它可以直接在另一个元件上或者也可以存在居中的元件。当一个元件被认为是“连接”另一个元件,它可以是直接连接到另一个元件或者可能同时存在居中元件。当一个元件被认为是“设置于”另一个元件,它可以是直接设置在另一个元件上或者可能同时存在居中元件。本文所使用的术语“垂直的”、“水平的”、“左”、“右”以及类似的表述只是为了说明的目的。It should be noted that when an element is referred to as being "fixed to" another element, it can be directly on the other element or a central element may also be present. When an element is considered to be "connected" to another element, it can be directly connected to the other element or an intermediate element may be present at the same time. When an element is considered to be "disposed on" another element, it can be directly disposed on the other element or a centered element may exist at the same time. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are for illustrative purposes only.
除非另有定义,本文所使用的所有的技术和科学术语与属于本申请的技术领域的技术人员通常理解的含义相同。本文中在本申请的说明书中所使用的术语只是为了描述具体的实施方式的目的,不是旨在于限制本申请。本文所使用的术语“或/及”包括一个或多个相关的所列项目的任意的和所有的组合。Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the technical field of this application. The terminology used in the specification of the application herein is only for the purpose of describing specific embodiments, and is not intended to limit the application. The term "or/and" as used herein includes any and all combinations of one or more related listed items.
本申请实施例提供了一种电极组件,包括第一极片、第二极片和隔离膜,所述第一极片与所述第二极片的极性相反,所述隔离膜设置于所述第一极片和所述第二极片之间,所述电极组件由所述第一极片、所述隔离膜和所述第二极片卷绕形成。所述第一极片包括第一集流体和第一活性物质层,所述第一活性物质层设置于所述第一集流体表面,所述第一极片的卷绕终止端位于所述第二极片的卷绕终止端远离卷心的外侧,所述第一极片的卷绕终止端上的所述第一活性物质层覆盖所述第一集流体朝向所述第二极片的一侧表面,所述第一极片的卷绕终止端上的所述第一集流体背离所述第二极片的一侧表面未涂覆所述第一活性物质层。所述电极组件进一步包括第一粘接件,所述第一粘接件设置于所述电极组件的外表面。The embodiment of the present application provides an electrode assembly, including a first pole piece, a second pole piece, and an isolation film. The first pole piece and the second pole piece have opposite polarities, and the isolation film is disposed at all Between the first pole piece and the second pole piece, the electrode assembly is formed by winding the first pole piece, the isolation film, and the second pole piece. The first pole piece includes a first current collector and a first active material layer, the first active material layer is disposed on the surface of the first current collector, and the winding end of the first pole piece is located at the first The winding end of the second pole piece is far away from the outside of the winding core, and the first active material layer on the winding end of the first pole piece covers one of the first current collectors facing the second pole piece On the side surface, the first active material layer is not coated on the side surface of the first current collector on the winding termination end of the first pole piece away from the second pole piece. The electrode assembly further includes a first adhesive member disposed on an outer surface of the electrode assembly.
上述电极组件将第一极片的卷绕终止端作为收尾端,使电芯组件最外圈的极片没有空铝箔的设计,节省单个电芯铝箔的耗材,并且大大减少了产生铝碎屑的可能,从而大量消除碎屑导致的危险短 路,避免电芯起火爆炸的危险发生,提高电芯在遭受极端使用情况下的安全性能。电极组件表面还设置第一粘接件,当电极组件装于包装袋时,第一粘接件可以将电极组件外表面与包装袋粘接起来。在遭受跌落、撞击等外力时,电极组件与外部包装袋可以紧密连接在一起,二者之间无相对位移,减少剪切破坏。The above-mentioned electrode assembly uses the winding end of the first pole piece as the finishing end, so that the outermost pole piece of the cell assembly has no empty aluminum foil design, which saves the consumables of a single cell aluminum foil and greatly reduces the generation of aluminum debris. Possibly, thereby eliminating a large amount of dangerous short circuits caused by debris, avoiding the risk of fire and explosion of the battery, and improving the safety performance of the battery under extreme conditions of use. The surface of the electrode assembly is also provided with a first adhesive member. When the electrode assembly is installed in the packaging bag, the first adhesive member can bond the outer surface of the electrode assembly with the packaging bag. When subjected to external forces such as a drop or impact, the electrode assembly and the external packaging bag can be tightly connected without relative displacement between the two, reducing shear damage.
本申请的一些实施方式作详细说明。在不冲突的情况下,下述的实施方式及实施方式中的特征可以相互组合。Some implementations of this application are described in detail. In the case of no conflict, the following embodiments and features in the embodiments can be combined with each other.
请参阅图1,在本申请的一实施例中,电极组件100包括第一极片10、第二极片20和隔离膜30。所述第一极片10与所述第二极片20的极性相反,所述隔离膜30设置于所述第一极片10和所述第二极片20之间,所述电极组件100由所述第一极片10、所述隔离膜30和所述第二极片20围绕一卷针卷绕形成,并且卷绕过程完成后,卷针从所述电极组件100中取出。所述第一极片10包括第一集流体11和第一活性物质层12,所述第一活性物质层12设置于所述第一集流体11表面,所述第一极片10的卷绕终止端位于所述第二极片20的卷绕终止端的远离卷心的外侧。Please refer to FIG. 1, in an embodiment of the present application, the electrode assembly 100 includes a first pole piece 10, a second pole piece 20 and an isolation film 30. The first pole piece 10 and the second pole piece 20 have opposite polarities, the isolation film 30 is disposed between the first pole piece 10 and the second pole piece 20, and the electrode assembly 100 The first pole piece 10, the isolation film 30, and the second pole piece 20 are wound around a winding needle, and after the winding process is completed, the winding needle is taken out of the electrode assembly 100. The first pole piece 10 includes a first current collector 11 and a first active material layer 12, the first active material layer 12 is disposed on the surface of the first current collector 11, and the first pole piece 10 is wound The terminal end is located on the outer side of the winding terminal end of the second pole piece 20 away from the winding core.
在本申请的实施例中,所述第一极片10为阴极片,所述第一集流体11可选为铝箔层,所述第一活性物质层12为阴极活性物质层,可选为LiCo0
2、LiFeP0
4等可脱嵌锂离子的电化学活性物质。所述第二极片20为阳极片,包括第二集流体21和第二活性物质层22,所述第二集流体可选为铜箔层,所述第二活性物质层22可选为石墨、软碳、硬碳、Li
4Ti
50
12等可嵌锂离子的电化学活性物质。
In the embodiment of the present application, the first pole piece 10 is a cathode sheet, the first current collector 11 may be an aluminum foil layer, and the first active material layer 12 is a cathode active material layer, which may be LiCo. 2, LiFeP0 4 other electrochemically active species can desorbing lithium ions. The second pole piece 20 is an anode piece and includes a second current collector 21 and a second active material layer 22. The second current collector may be a copper foil layer, and the second active material layer 22 may be graphite. , Soft carbon, hard carbon, Li 4 Ti 5 0 12 and other electrochemically active materials that can intercalate lithium ions.
所述第一极片10的卷绕终止端13为所述电极组件100的最外层的极片的结构。所述第一极片10的卷绕终止端13上的所述第一活性物质层12覆盖所述第一集流体11朝向所述第二极片20的一侧表面,所述第一极片10的卷绕终止端13上所述第一集流体11背离所述第二极片20的一侧表面未涂覆所述第一活性物质层12。The winding end 13 of the first pole piece 10 is the structure of the outermost pole piece of the electrode assembly 100. The first active material layer 12 on the winding end 13 of the first pole piece 10 covers a side surface of the first current collector 11 facing the second pole piece 20, and the first pole piece The surface of the first current collector 11 facing away from the second pole piece 20 on the winding end 13 of 10 is not coated with the first active material layer 12.
所述电极组件100进一步包括第一粘接件41和第二粘接件42,所述第一粘接件41设置于所述电极组件100的外表面,用于粘接电极组件100与包装袋以减小或消除二者之间的装配间隙,所述第二粘接件42连接所述第一极片10的卷绕终止端并覆盖所述电极组件100的部分外表面。The electrode assembly 100 further includes a first adhesive member 41 and a second adhesive member 42. The first adhesive member 41 is disposed on the outer surface of the electrode assembly 100 for bonding the electrode assembly 100 and the packaging bag. In order to reduce or eliminate the assembly gap between the two, the second adhesive member 42 is connected to the winding terminal end of the first pole piece 10 and covers a part of the outer surface of the electrode assembly 100.
在本申请的实施例中,所述第一粘接件41为半液体粘性材料,以点涂、涂覆等方式设置于所述电极组件100的外表面,在电池遭受跌落、撞击等外力时,电极组件100与外部包装袋紧密连接在一起,二者之间无相对位移,减少剪切破坏。所述第一粘接件41可以为热熔层,材料可以是橡胶系粘结剂、丙烯酸系粘结剂等,在一定压力(≤3MPa)与温度(≤120℃)条件下,可以产生粘性,将电极组件100外表面与包装袋牢固粘接在一起。所述第一粘接件41的厚度≤20um,粘接力为100-1000N/m,拉伸断裂应力≤4000N/m。In the embodiment of the present application, the first adhesive member 41 is a semi-liquid viscous material, which is arranged on the outer surface of the electrode assembly 100 by means of spot coating, coating, etc., when the battery is subjected to external forces such as a drop or impact. , The electrode assembly 100 and the external packaging bag are tightly connected, and there is no relative displacement between the two, reducing shear damage. The first adhesive member 41 can be a hot melt layer, and the material can be a rubber-based adhesive, an acrylic adhesive, etc., under certain pressure (≤3MPa) and temperature (≤120°C) conditions, it can produce viscosity , The outer surface of the electrode assembly 100 and the packaging bag are firmly bonded together. The thickness of the first adhesive member 41 is less than or equal to 20 um, the adhesive force is 100-1000 N/m, and the tensile fracture stress is less than or equal to 4000 N/m.
在一可选实施例中,所述第二粘接件42为热熔胶或绝缘胶,可选为厚度为15um~25um的超薄热熔胶,材料可以是橡胶系粘结剂,与PET联用。在一定压力(≤3MPa)与温度(≤120℃)条件下,所述第二粘接件42可以产生粘性。换句话说,所述第二粘接件42的热熔温度小于或等于120℃,热熔压力小于或等于3MPa。In an optional embodiment, the second adhesive member 42 is hot melt adhesive or insulating adhesive, and may be ultra-thin hot melt adhesive with a thickness of 15um to 25um. The material may be a rubber-based adhesive and PET Combined. Under certain pressure (≤3MPa) and temperature (≤120°C) conditions, the second adhesive member 42 can be viscous. In other words, the hot melt temperature of the second adhesive member 42 is less than or equal to 120° C., and the hot melt pressure is less than or equal to 3 MPa.
请再次参阅图1,所述电极组件100的外表面包括第一平面101、第二平面102、第一弧面103和第二弧面104。沿所述电极组件100的厚度方向(图1箭头A指示的方向),所述第一平面101与所述第二平面102相对设置,沿所述电极组件100的宽度方向(图1箭头B指示的方向),所述第一弧面103与所述第二弧面104相对设置,并且所述第一弧面103和所述第二弧面104连接于第一平面101与第二平面102之间。Please refer to FIG. 1 again. The outer surface of the electrode assembly 100 includes a first flat surface 101, a second flat surface 102, a first curved surface 103 and a second curved surface 104. Along the thickness direction of the electrode assembly 100 (the direction indicated by arrow A in FIG. 1), the first plane 101 and the second plane 102 are disposed opposite to each other, and along the width direction of the electrode assembly 100 (the direction indicated by arrow B in FIG. 1) Direction), the first arc surface 103 and the second arc surface 104 are disposed oppositely, and the first arc surface 103 and the second arc surface 104 are connected between the first plane 101 and the second plane 102 between.
所述第一极片10卷绕终止端大致位于所述第一平面101与第一弧面103的交界处,所述第二粘接件42连接所述第一极片10的卷 绕终止端并贴附于所述第一弧面103,避免第二粘接件42增加电极组件100的厚度。所述第一粘接件41与所述第二粘接件42连接并覆盖所述第一平面101、第二平面102和第二弧面104。换句话说,所述电极组件100外表面上未贴附第二粘接件42的区域被第一粘接件41覆盖。在其他实施例中,所述第一极片的卷绕终止端还可以位于第一平面101或第二平面102,相应地,第二粘接件42也贴附于所述第一平面101或所述第二平面102。The winding termination end of the first pole piece 10 is approximately located at the junction of the first plane 101 and the first arc surface 103, and the second adhesive member 42 is connected to the winding termination end of the first pole piece 10 It is attached to the first curved surface 103 to prevent the second adhesive member 42 from increasing the thickness of the electrode assembly 100. The first bonding member 41 is connected to the second bonding member 42 and covers the first plane 101, the second plane 102 and the second arc surface 104. In other words, the area on the outer surface of the electrode assembly 100 where the second adhesive member 42 is not attached is covered by the first adhesive member 41. In other embodiments, the winding end of the first pole piece may also be located on the first plane 101 or the second plane 102, and accordingly, the second adhesive member 42 is also attached to the first plane 101 or The second plane 102.
进一步地,为了避免第二极片20的端部析锂产生的毛刺刺穿隔离膜30并连接第一极片10而发生短路,所述第二极片20的卷绕终止端沿极片卷绕方向伸出所述第一极片10的卷绕终止端13,伸出的长度L1大于或等于2mm。所述隔离膜30的卷绕终止端31沿卷绕方向伸出所述第二极片20的卷绕终止端,并贴附于所述第二粘接件42的内表面,所述隔离膜30的卷绕终止端31的长度L2大于或等于4mm。所述第二极片20的卷绕终止端被所述隔离膜30的卷绕终止端31覆盖,以保护和绝缘所述第二极片20的卷绕终止端。Further, in order to prevent the burrs generated by the lithium evolution at the end of the second pole piece 20 from piercing the isolation film 30 and connecting the first pole piece 10 to cause a short circuit, the winding end of the second pole piece 20 is rolled along the pole piece. The winding end 13 of the first pole piece 10 extends in the winding direction, and the extension length L1 is greater than or equal to 2 mm. The winding termination end 31 of the isolation film 30 extends from the winding termination end of the second pole piece 20 in the winding direction, and is attached to the inner surface of the second adhesive member 42. The isolation film The length L2 of the winding end 31 of 30 is greater than or equal to 4 mm. The winding termination end of the second pole piece 20 is covered by the winding termination end 31 of the isolation film 30 to protect and insulate the winding termination end of the second pole piece 20.
请参阅图1和图3,所述电极组件100进一步包括第一极耳50和第二极耳60,所述第一极耳50连接所述第一极片10,所述第二极耳60连接所述第二极片20。沿所述电极组件100的厚度方向,所述第一极耳50与所述第二极耳60的投影不重叠,沿所述电极组件100的长度方向(图3箭头C指示方向),所述第一极耳50和所述第二极耳60伸出所述电极组件100的同一端。在其他实施例中,所述第一极耳50和所述第二极耳60可以从所述电极组件100的不同端伸出,本申请不限定于此。1 and 3, the electrode assembly 100 further includes a first tab 50 and a second tab 60, the first tab 50 is connected to the first tab 10, and the second tab 60 The second pole piece 20 is connected. Along the thickness direction of the electrode assembly 100, the projections of the first tab 50 and the second tab 60 do not overlap, and along the length direction of the electrode assembly 100 (the direction indicated by arrow C in FIG. 3), the The first tab 50 and the second tab 60 protrude from the same end of the electrode assembly 100. In other embodiments, the first tab 50 and the second tab 60 may protrude from different ends of the electrode assembly 100, and the application is not limited thereto.
进一步地,所述第一极片10的卷绕起始端设有第一空箔区14,所述第二极片20的卷绕起始端设有第二空箔区23,所述第一极耳50设置于所述第一空箔区14,所述第二极耳60设置于所述第二空箔区23。所述电极组件100包括第一绝缘件70,所述第一绝缘件 70设置于所述第一空箔区14并覆盖所述第一极耳50,防止第一极耳50上的毛刺刺穿隔离膜30与第二极片20接触而发生短路。在一可选实施例中,所述第一绝缘件70可以为绝缘胶带,从第一极耳50延伸至第一活性物质层12的起始端,几乎包覆整个第一空箔区14,或者第一极耳50与第一活性物质层12的起始端之间另外设置一条第一绝缘件70,使得第一空箔区14得到有效保护,避免出现碎裂、短路等情况。Further, the winding start end of the first pole piece 10 is provided with a first empty foil area 14, and the winding start end of the second pole piece 20 is provided with a second empty foil area 23, and the first pole piece The ear 50 is arranged in the first empty foil area 14, and the second tab 60 is arranged in the second empty foil area 23. The electrode assembly 100 includes a first insulating member 70 disposed in the first empty foil area 14 and covering the first tab 50 to prevent burrs on the first tab 50 from piercing The isolation film 30 is in contact with the second pole piece 20 and a short circuit occurs. In an alternative embodiment, the first insulating member 70 may be an insulating tape, extending from the first tab 50 to the starting end of the first active material layer 12, and covering almost the entire first empty foil region 14, or A first insulating member 70 is additionally provided between the first tab 50 and the starting end of the first active material layer 12, so that the first empty foil region 14 can be effectively protected to avoid cracks, short circuits, and the like.
在一可选实施例中,所述第二空箔区23伸出所述第一空箔区14,所述第二极耳60设置于所述第二空箔区23伸出所述第一空箔区14的区域,即使第二极耳60上的毛刺刺穿隔离膜30,第二极耳60接触的也是第二极片20,不会因为接触第一极片10而发生短路。所述电极组件100进一步包括第二绝缘件80,所述第二绝缘件80覆盖所述第一空箔区14的端部,避免第一空箔区14端部的毛刺刺破隔离膜30与第二极片20接触。In an alternative embodiment, the second empty foil area 23 extends out of the first empty foil area 14, and the second tab 60 is arranged on the second empty foil area 23 and extends out of the first empty foil area. In the area of the empty foil area 14, even if the burrs on the second tab 60 pierce the isolation film 30, the second tab 60 is in contact with the second pole piece 20 and will not be short-circuited due to contact with the first pole piece 10. The electrode assembly 100 further includes a second insulating member 80 that covers the end of the first empty foil region 14 to prevent burrs at the end of the first empty foil region 14 from piercing the isolation film 30 and The second pole piece 20 contacts.
请参阅图2,在本申请的其中一个实施例中,所述第一极耳50设置于所述第一集流体11上涂覆第一活性物质层12的区域,所述第二极耳60设置于所述第二集流体21上涂覆第二活性物质层22的区域。所述第一极耳50和所述第二极耳60处均设有第一绝缘件70,以避免短路问题。在连接第一极耳50与第一集流体11时,需要先将部分第一活性物质层12去除,使得部分第一集流体11露出所述第一活性物质层12,然后第一极耳50焊接于露出部分的第一集流体11。第二极耳60与第二集流体21的连接方式类似,此处不再赘述。在其他实施例中,所述第一极耳50和所述第二极耳60还可以一个设置在电极组件100卷心处的空箔区,另一个设置在极片的其他位置,本申请不限定于此。Please refer to FIG. 2, in one of the embodiments of the present application, the first tab 50 is disposed on the area where the first active material layer 12 is coated on the first current collector 11, and the second tab 60 The area where the second active material layer 22 is coated is arranged on the second current collector 21. Both the first tab 50 and the second tab 60 are provided with a first insulating member 70 to avoid short circuit problems. When connecting the first tab 50 and the first current collector 11, it is necessary to remove part of the first active material layer 12 first, so that part of the first current collector 11 exposes the first active material layer 12, and then the first tab 50 The first current collector 11 is welded to the exposed part. The connection mode of the second tab 60 and the second current collector 21 is similar, and will not be repeated here. In other embodiments, one of the first tab 50 and the second tab 60 may be set in the empty foil area at the core of the electrode assembly 100, and the other may be set in another position of the pole piece. This application does not Limited to this.
请参阅图4和图5,图中虚线指示位置是相邻两个第一极片10制造过程中的裁切位置。当第一极耳50设置于第一空箔区14时, 由于对比实施例的电极组件最外圈设有一段空铝箔,图4显示的对比实施例中空铝箔区域的长度L3明显大于图5显示的本申请实施例中空铝箔区域的长度L4,本申请实施例中空铝箔区域的长度L4只需要满足电极组件100卷绕起始端的参数要求即可,既节约了铝箔的耗材,又去除了最外圈的空铝箔,在极端破坏情况下,大大减少了产生铝碎屑的可能,从而大量消除碎屑导致的危险短路,避免电极组件100起火爆炸的危险发生,提高电极组件100在遭受极端使用情况下的安全性能。Please refer to FIG. 4 and FIG. 5, the position indicated by the dotted line in the figure is the cutting position of two adjacent first pole pieces 10 during the manufacturing process. When the first tab 50 is arranged in the first empty foil area 14, since the outermost circle of the electrode assembly of the comparative embodiment is provided with a section of empty aluminum foil, the length L3 of the hollow aluminum foil area of the comparative embodiment shown in FIG. 4 is obviously greater than that shown in FIG. 5. The length L4 of the hollow aluminum foil area in the embodiment of the present application, the length L4 of the hollow aluminum foil area in the embodiment of the present application only needs to meet the parameter requirements of the winding start end of the electrode assembly 100, which not only saves aluminum foil consumables, but also removes the outermost The hollow aluminum foil of the circle greatly reduces the possibility of aluminum debris in the case of extreme damage, thereby eliminating a large number of dangerous short circuits caused by the debris, avoiding the risk of fire and explosion of the electrode assembly 100, and improving the extreme use of the electrode assembly 100 Safety performance.
请参阅图6和图7,当第一极耳50设置于第一集流体11涂覆第一活性物质层12的区域时,由于对比实施例的电极组件最外圈设有一段空铝箔,图6显示的对比实施例中,相邻两个第一极片10之间存在一段单面区和一段空铝箔,单面区为第一极片10的卷绕终止端13,而图7显示的本申请的实施例中,相邻两个第一极片10之间的空铝箔取消,仅有一段单面区(第一极片10的卷绕终止端13),使得第一集流体11下表面的第一活性物质层12可以连续,简化了第一极片10的制造过程,有利于提高生产效率。6 and 7, when the first tab 50 is provided in the area where the first current collector 11 is coated with the first active material layer 12, since the outermost ring of the electrode assembly of the comparative embodiment is provided with a section of empty aluminum foil, the figure In the comparative example shown in Fig. 6, there is a section of single-sided area and a section of empty aluminum foil between two adjacent first pole pieces 10, and the single-sided area is the winding end 13 of the first pole piece 10. In the embodiment of the present application, the empty aluminum foil between two adjacent first pole pieces 10 is eliminated, and there is only a single-sided area (the winding end 13 of the first pole piece 10), so that the first current collector 11 The first active material layer 12 on the surface can be continuous, which simplifies the manufacturing process of the first pole piece 10 and helps to improve production efficiency.
请参阅图8,在一对比实施例中,电极组件外层尾部存在部分空铝箔105(两面均无活性物质涂层),且尾部空铝箔与其尾部的涂层边缘贴附一层绝缘胶带106。所述空铝箔105和所述绝缘胶带106均位于电极组件的第一平面101或第二平面102。Referring to FIG. 8, in a comparative embodiment, a part of the hollow aluminum foil 105 exists at the outer tail of the electrode assembly (no active material coating on both sides), and a layer of insulating tape 106 is attached to the tail hollow aluminum foil and the coating edge of the tail. The hollow aluminum foil 105 and the insulating tape 106 are both located on the first plane 101 or the second plane 102 of the electrode assembly.
对比实施例与本申请实施例的电极组件100的撞击测试的具体内容为:将满充电极组件放置于平面铁板上,将直径为φ15.8±0.1mm、长度至少6cm圆棒垂直于试样(极耳位置),用9.1±0.1Kg的重锤,距离圆棒与试样交叉处61±2.5cm,垂直自由状态落下,对比电极组件通过率。通过判定标准为完成测试后,电极组件不起火、不爆炸。The specific content of the impact test of the electrode assembly 100 of the comparative example and the embodiment of the present application is: placing the fully charged electrode assembly on a flat iron plate, and placing a round rod with a diameter of φ15.8±0.1mm and a length of at least 6cm perpendicular to the test For the sample (position of the tab), use a weight of 9.1±0.1Kg at a distance of 61±2.5cm from the intersection of the round bar and the sample, and fall in a vertical free state to compare the pass rate of the electrode assembly. The passing criterion is that after the test is completed, the electrode assembly does not catch fire or explode.
对比实施例与本申请实施例的电极组件100的撞击测试数据如 下表所示。The impact test data of the electrode assembly 100 of the comparative example and the example of the present application is shown in the following table.
类别category
|
撞击通过数Number of passes
|
通过比例Pass ratio
|
实施例Example
|
9/10pass9/10pass
|
90%90%
|
对比例Comparison
|
0/10pass0/10pass
|
0%0%
|
对比实施例与本申请实施例的电极组件100的跌落测试的具体内容为:电极组件半充,装入专用夹具中,进行适当固定,然后将夹具置于1m处进行跌落测试,六面四角跌一次为一轮,共跌四轮,对比电芯通过率;判定标准为完成测试后,顶封冲开,漏液,24h压降>30mV,铝箔撕裂。The specific content of the drop test of the electrode assembly 100 of the comparative example and the embodiment of the present application is: the electrode assembly is half-charged, put into a special fixture, properly fixed, and then the fixture is placed at a distance of 1m for a drop test. One round at a time, a total of four rounds were dropped to compare the pass rate of the cell; the criterion is that after the test is completed, the top seal is flushed, the liquid leaks, the 24h pressure drop is >30mV, and the aluminum foil is torn.
第一组测试中电极组件的厚度为3mm(绕卷11层),测试结果如下表所示。The thickness of the electrode assembly in the first set of tests is 3mm (11 layers rolled), and the test results are shown in the table below.
第二组测试中电极组件的厚度为5mm(绕卷19层),测试结果如下表所示。The thickness of the electrode assembly in the second set of tests is 5mm (wound 19 layers), and the test results are shown in the table below.
结合图4至图8和上述表面中的数据,本申请的实施例与对比实施例相比,电极组件100最外圈无空铝箔设计,减少了产生铝碎 屑的可能,从而消除碎屑导致的危险短路,避免电极组件100起火爆炸的危险发生,提高电极组件100在遭受极端使用情况下的安全性能,同时电极组件100外表面设置的第一粘接件41使电极组件100与外部包装袋可以紧密连接在一起,二者之间无相对位移,减少剪切破坏。In combination with the data in FIGS. 4 to 8 and the above-mentioned surface, the embodiment of the present application is compared with the comparative example, the outermost ring of the electrode assembly 100 is designed with no hollow aluminum foil, which reduces the possibility of aluminum debris, thereby eliminating debris caused by To avoid the danger of fire and explosion of the electrode assembly 100, improve the safety performance of the electrode assembly 100 under extreme use conditions. At the same time, the first adhesive 41 provided on the outer surface of the electrode assembly 100 makes the electrode assembly 100 and the external packaging bag Can be tightly connected together, there is no relative displacement between the two, reducing shear damage.
请参阅图9,本申请的实施例还提供一种电池200,包括包装体201和所述实施例中的电极组件100,所述电极组件100收容在所述包装体201中,所述电极组件100的极耳伸出所述包装体201。Referring to FIG. 9, an embodiment of the present application further provides a battery 200, including a packaging body 201 and the electrode assembly 100 in the embodiment. The electrode assembly 100 is housed in the packaging body 201, and the electrode assembly The tabs of 100 extend out of the packaging body 201.
以上实施方式仅用以说明本申请的技术方案而非限制,尽管参照以上较佳实施方式对本申请进行了详细说明,本领域的普通技术人员应当理解,可以对本申请的技术方案进行修改或等同替换都不应脱离本申请技术方案的精神和范围。The above embodiments are only used to illustrate the technical solutions of the application and not to limit them. Although the application has been described in detail with reference to the above preferred embodiments, those of ordinary skill in the art should understand that the technical solutions of the application can be modified or equivalently replaced None should deviate from the spirit and scope of the technical solution of this application.